Building Projects

Build a Timber Frame Style Backyard Pavilion Part 2

By October 25, 2018 February 26th, 2019 No Comments

Build your own Timber Frame Style Garden Pavilion. Plans available for download in PDF Format.

Part 2 of 3

See the How to Video.

In Part 1 of this Garden Pavilion Build we got the posts up and the side girts installed.

Posts and Side Girts

Posts and Side Girts

Part 2 – Build the Timber Frame Style Gazebo

Cut Upper Beams

The next step is to cut the upper beams to length and mark their crown.

Cut main roof beams to length

Cut main roof beams to length

The ends have a quarter ellipse cut into them.

Trace profile on ends of beams from a plywood pattern

Trace profile on ends of beams from a plywood pattern

I laid out and cut a pattern from plywood according to the drawings. These curves are then traced on the ends of the beams.

Sketchup Image - The top beams have a shallow groove where they sit on the post tops

The top beams have a shallow groove where they sit on the post tops

This shallow groove is made using saw and chisel

This shallow groove is made using saw and chisel

I’ll lay out and cut the shallow groove where it sits on the top of the post. I like the beams to sit down on the post an inch. I like this look and you may have seen me do this on other projects. I think it’s worth the extra time and effort.

As with all the grooves or laps on this build, I make a series of close parallel cuts using a large speed square with the circular saw set to depth. Then break these off with a hammer or wooden mallet. Then clean up the groove with a chisel.

DIY Gazebo Build - Curved profile on ends are cut with jigsaw and a long blade

Curved profile on ends are cut with jigsaw and a long blade

Now to cut these quarter ellipse end profiles. For this I use a jigsaw with a long blade. I did a full review of this jigsaw. See the video.

I cut these from the end inward. With a handsaw I make a shallow straight, square cut in the end of the beam first. This helps to start the blade squarely and improves the accuracy of the cut.

During this hot and dry summer there were forest fires burning throughout the west. The smoke in the air on a few of these days made it look like sunset all day long. I decided to leave the footage as the camera saw it and to not colour correct it.

So it was kinda fitting that I burnt the wood on these cuts by turning a bit too sharply at the end of the curve. I sanded the char marks off afterward.

The holes for the lag bolts are drilled prior to assembly

Holes for the lag bolts are pre-drilled before assembly

I’ll attach the beams to the tops of the posts with a long lag bolt. I countersink the head and washer with a forstner bit, then drill a pilot hole, then finish with a bit slightly smaller than the diameter of the lag bolt shank.

Beams are chamfered with power plane. The bow in these beams can be seen.

Beams are chamfered with power plane. The bow in these beams can be seen.

The beams are then chamfered too. You can see the bow in these beams that I oriented up as the crown.

Angle grinder with sanding disc is very good for quickly chamfering in tight spots

Angle grinder with sanding disc is very good for quickly chamfering in tight spots

I use a grinder with sanding disk to chamfer the curves and tighter corners.

Put Beams in Place
Rear beam laid in place with some assistance from neighbour

Rear beam laid in place with some help

Front one too

Front one too

I enlisted the help of my neighbour Calvin to set these beams on the top of the posts. And this went well and they fit the first time.

Long lag bolts hold beam to post

Long lag bolts secure beams to posts

I drill into the post with a long bit and run in the lag bolt with a socket wrench.

Corner Braces

I made most of the braces for this Pavilion and my Woodshed Project at the same time. If you saw the Woodshed Build Series then you might recognize some of these images. But I’ll quickly go through the steps again for this project.

I made the braces using two by eight red cedar.

Trace corner brace plywood pattern onto 2x8 red cedar

Trace corner brace plywood pattern onto stock

I laid out and cut a plywood pattern according to the plans. I trace the pattern then cut opposing forty five degree angles on the miter saw.

45's are cut with the mitre saw

Cut angles on the miter saw

This ensures the brace will be ninety degrees.

The curves of the brace are rough cut on a bandsaw

The curves of the brace are rough cut on a band saw

I cut the curved sections on the band saw.

I sand this cut smooth with a small hobby belt sander.

1" sanding belt of a hobby sander smooths bandsaw marks

A little smoothing on a 1″ sanding belt of a hobby sander

The flexible sanding belt follows the curve of the brace quite well. The braces will be attached to the posts and beams with a long lag bolt at a twenty degree angle to help pull the brace tightly into the corner.

Setting the drill press table to 20 degrees

Setting the drill press table to 20 degrees

I tilt the table on my drill press to this angle, mark the hole center, and clamp some simple stops to the table to hold the pieces in place.

Stop blocks added to hold brace steady

Stop blocks added to hold brace in position

A countersink with a forstner bit drops the head of the bolt neatly below the surface. Then I switch bits to drill the pilot hole for the shank of the lag bolt.

Brace is countersunk to bury the head of the lag bolt

Brace is countersunk to bury the head of the lag bolt

Using my angle grinder with a sanding disc, I bevel the edges of each corner braces except the edge that mates with a post, girt, or beam. So all the outside edges.

Stack of corner braces are chamfered with angle grinder and sanding disc attachment

Stack of corner braces are chamfered with angle grinder and sanding disc attachment

Install Corner Braces

I mark the post and the beam two inches in from the outside edge to guide the brace location. I applied some exterior wood glue then hold it securely in place.

Corner brace is held in place and post is drilled with long 1/4" bit

Corner brace is held in place and post is drilled with long 1/4″ bit

Then drill into the post and beam and drive in a lag bolt with an impact driver. I’ll hand tighten with a socket wrench to prevent thread rip out.

Lag bolts are hand tightened to prevent over torquing

Lag bolts are hand tightened to prevent over torquing

For this structure, I think this simple brace is more than enough to give the frame rigidity. A brace with a proper tenon mortised into the post and the beam is always the best option, but for this build I think a flat mounted brace with a long, angled, lag bolt is sufficient.

Lag bolt is driven in with impact driver - Dewalt Cordless

Lag bolt is driven in with impact driver

On the plans I have included a slightly larger brace for the inside corners as an alternative.

The braces that mate with the girts are installed flush with the outer face of the post, as the girts are the same thickness as the braces.

Corner braces are centered on narrower side girts

Corner braces are centered on narrower side girts

Brace Options

As another option, I have included another brace variation in the plans that allows for a flush mount onto the inside of the girt or front roof beam.

Another brace variation for front roof beam and front post

Optional brace for front roof beam and front post

This matches the look of the other braces from the outside.

Front Roof Beams

The front roof beams are made from two by eight stock.

Front roof beams - Pavilion Construction

Front roof beams

A similar ellipse profile is cut in the ends as the upper beams.

Ends cut with a jigsaw

Quarter ellipse profile cut with jigsaw

And the beam that mounts on the front post has a small groove cut to make clearance for the girt. These are also chamfered with the power plane and angle grinder.

Dressing 2x8 beams with plane

Front roof beams chamfered before installing

First I attach the beam to the front posts with construction adhesive and lag bolts.

Roof beam is attached to front posts with glue and bolts

Roof beam is attached to front posts with glue and bolts

To help attach the lower front beam I screwed on some temporary boards to the bottom edge of the girts. This allows me to rest this beam on these supports while I drill and run in lag bolts.

Lower front roof beam is set on supports

Lower front roof beam is set on supports then drilled and screwed in place

In addition to these lag bolts I add a galvanized corner brace to the inside of the lower front roof beam where it meets the girt.

Metal supports

Additional bracing supports lower front roof beam where it connects to the end of the girts

Main Roof Rafters

The twelve best fir two by eights for the rafters are pulled from the pile. These are inspected, marked for their crown then cut to length.

main roof rafters getting stained

Staining main roof rafters

The ellipse profile is copied onto the ends and cut with the jigsaw. They are stained and let dry overnight.

I also rolled on a coat of stain on the pavilion frame the same day. It’s easier to do now than after the rafters go up.

Twelve 2x8 full dimension fir roof rafters make up the main roof

Twelve 2×8 full dimension fir roof rafters make up the main roof

Detail of how the rafters sit on the rear beam

Detail of how the rafters sit on the rear beam

Each rafter is hauled up and positioned across the top beams.

Two birds-mouth cuts (plumb and seat)

Each rafter has two birds-mouth cuts

The birds-mouths are marked then it’s taken down to the sawhorses.

The rafters are marked by laying them over the beams. Then taken down to sawhorses to cut

The rafters are marked by laying them over the beams. Then taken down to sawhorses to cut

They are cut with a circular saw, then finished with the jigsaw.

To start I clamp some blocks to the ends of the top beams. On the rafter I pre-marked the point where it will contact the upper beam. At this mark I cut a small saw kerf to help hold it in place while I mark the birds-mouth.

Circular saw roughs out the seat and plumb cut first

Circular saw roughs out the seat and plumb cut first

I haul up the first rafter and clamp it to the block to hold it. I have some wooden home-made scaffolding and planks to stand on so I set those up.

Cuts are then finished with a jigsaw

Cuts are then finished with a jigsaw

I take the rafter down to the sawhorses and cut the birds-mouth. Then permanently attach the blocks to the beams.

Install Main Roof Rafters

Rafters are hauled back up and screwed to the beams. Support blocks are added to each beam as the rafters are installed.

I secure each rafter to the beam and the support blocks between rafters. I straighten them with small pipe clamps

I secure each rafter to the beam and the support blocks between rafters. I straighten them with small pipe clamps

I’ll be using the blocking along with short pipe clamps to straighten each rafter as I go along. I put the straightest rafters on the outside edges of the pavilion. And the most twisted ones on the inside.

Timber Frame Gazebo - This rafter was twisted and bowed

Timber Frame Gazebo – This rafter was twisted and bowed

This third rafter on the east side was twisted AND bowed. But not so bad that I couldn’t use it.

This rafter had the most twist, maybe more than 10 degrees or so.

The pipe clamp worked very well at straightening the twist and holding it in place for screws

The pipe clamp worked very well at straightening the twist and holding it in place for screws

But the pipe clamp worked like a charm to straighten it.

So this process was repeated for each of the twelve rafters. It took the better part of a day but it went well.

One by one the rafters where hauled up and secured with blocking and screws

One by one the rafters where hauled up and secured with blocking and screws

Full dimension 2×8 fir is heavy so I slept well that night.

Last corner braces added

Last corner braces added

I had a few outside braces left to put on so I did that next.

See Part 3

 

%d bloggers like this: